It is known to provide a hole punching machine which is arranged to punch a pattern of holes in a sheet of material, the pattern corresponding to a pattern of pilot holes in a template. The sheet of material to be punched is placed in a guide frame which is movable relative to a table, and punching apparatus is mounted on the table for punching the sheet, the punched holes being made in a fixed position relative to the table. A stylus is attached to the guide frame, and by moving the frame, the stylus can be located in turn in each of the pilot holes; the punch being operated each time the stylus is located in a pilot hole so as to map the pattern of holes on the template on to the sheet of material.
This known machine has several disadvantages, particularly when used to punch holes in sheets which are several times larger than the template. For example, with a sheet of material which is twice the size of the template, the sheet must be mounted on the guide frame twice to permit a pattern of holes to be reproduced over the whole sheet. Thus, errors in the positions of holes punched in the sheet are likely to occur, and since the sheet must be accurately mounted twice in the guide frame, the manufacturing time is increased. Moreover, the guide frame of the known punching machine suffers from the disadvantage that it unpredictably permits rotation of the sheet to be punched relative to the template during punching, and hence distortions and positional errors in the punched pattern can occur.